-LRB- CNN -RRB- -- Efforts to rescue a research crew aboard a ship stuck in ice off Antarctica stalled Thursday after sea ice conditions made a key element of the rescue plan risky , Australian maritime officials said .

The rescue plan called for a helicopter to ferry the passengers from the MV Akademik Shokalskiy to a Chinese vessel , where they would then board a barge to take them to an Australian icebreaker , the Australian Maritime Safety Authority -LRB- AMSA -RRB- said in a written statement .

But the shifting ice conditions prevented the barge from being able to reach the Chinese vessel , the statement said .

`` Alternative measures to complete the rescue operation are now being investigated by AMSA and the ships involved , '' the statement said .

The news is the latest chapter in a saga that began Christmas Eve after the Russian-flagged MV Akademik Shokalskiy got stuck in 10 feet of ice .

Even if the rescue begins Friday , it will still be weeks before the research team will make it to Hobart , Australia , John Young of the Australian Maritime Safety Authority said .

`` Mid-January is our best guess , '' Young told reporters on a conference call .

The rescue plan called for the helicopter , which can transport 12 people each trip , to ferry the ship 's 52 passengers -- who include the research team and journalists -- to the Chinese icebreaker called the Snow Dragon , or Xue Long , the maritime agency said . The 22 Russian crew members of the Akademik Shokalskiy will stay aboard , it said .

The passengers are then to be transported by barge from the Chinese ship to the Australian icebreaker Aurora Australis .

That 's because the Chinese helicopter ca n't land on the Australian icebreaker because of load restrictions , and ice conditions make it unsafe to land it next to the ship , AMSA said .

`` The preferred option is to wait for conditions that will allow the rescue to be completed in a single operation to reduce unnecessary risk , '' the maritime agency said .

The master of the Akademik Shokalskiy has decided to keep the crew members on board until the pack ice eventually breaks up and allows the ship to move again , Young said . The vessel has enough supplies to keep the crew going for `` a very long time , '' he said .

Failed rescues

The planned helicopter rescue follows a failed attempt by the Chinese icebreaker , which made it six nautical miles from the trapped vessel before being stopped by the ice .

That was followed by an effort by the Australian icebreaker , which was forced Monday to suspend efforts to reach the expedition because of bad weather . The Aurora Australis got within 10 nautical miles of the ship before it turned back .

Over the weekend , an effort by the French icebreaker Astrolabe was called off by the maritime agency .

In preparation for the helicopter rescue , members of the research team as well as the crew of the Akademik Shokalskiy marked a makeshift helipad on the ice where the helicopter can land .

Video clips posted online by the research team showed people , with arms locked , walking to tamp down the snow .

`` As we understand , the helipad was suitable yesterday and will be suitable today , '' AMSA 's Richard Wallace said .

Once the passengers are safely aboard the Aurora Australis , the ship will complete a resupply mission to Casey Station , an Australian base in Antarctica , before making its way to Hobart , the maritime agency said .

Viral sensations

The exploits of the research crew have gone viral , thanks in large part to Twitter and YouTube posts by those aboard the stranded vessel .

Chris Turney , an Australian professor of climate change at the University of New South Wales , has tweeted photos of the stranded ship , the crew and penguins , who he said -- according to one post on Twitter -- `` to check out what 's going on . ''

`` The group on this ship is incredibly collegiate , '' said Alok Jha , a science correspondent for The Guardian newspaper , told CNN 's Anderson Cooper 360 . `` There are a lot of skills and things people are sharing with each other . ''

Turney has said there are regular briefings on the status of rescue attempts , and in the meantime , people are doing what they can to keep busy . That includes yoga and Spanish classes , Jha and Turney said .

The group even managed to ring in 2014 with good cheer .

`` We 're the A , A , E who have traveled far , having fun doing science in Antarctica ! '' a dozen or so of them sang in a video posted on YouTube . `` Lots of snow and lots of ice , lots of penguins , which are very , very nice !

`` Really good food and company , but a bloody great shame we are still stuck here ! Ice cold , cha cha cha ! Ice cold , cha cha cha ! ''

Spirits strong among passengers on ship stuck in Antarctic ice

CNN 's Radina Gigova and Jethro Mullen contributed to this report .

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NEW : Ice conditions have stalled a helicopter rescue , officials say

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NEW : Alternative rescue measures are being considered , maritime officials say

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NEW : `` The preferred option is to wait for conditions that will allow the rescue , '' they say

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Efforts by Australian and Chinese icebreakers to get to the crew have failed